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1.
J Formos Med Assoc ; 122(8): 785-789, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36907791

RESUMO

BACKGROUND: The rate of induction of labour has increased over the decades and numerous medications are available in the market. This study compares the efficacy and safety between dinoprostone slow-release pessary (Propess) and dinoprostone tablet (Prostin) for labour induction at term in nulliparous women. METHODS: This was a prospective single-blind randomized controlled trial conducted in a tertiary medical centre in Taiwan from September 1, 2020 to February 28, 2021. We recruited nulliparous women at term with a singleton pregnancy, fetus in cephalic presentation, an unfavourable cervix, and the cervical length had been measured by transvaginal sonography three times during labour induction. The main outcomes are duration from induction of labour to vaginal delivery, vaginal delivery rate, maternal and neonatal complication rates. RESULTS: In both groups, Prostin and Propess, 30 pregnant women were enrolled. The Propess group had higher vaginal delivery rate but it did not meet statistically significant difference. The Prostin group had significantly higher rate of adding oxytocin for augmentation (p = 0.0002). No significant difference was observed in either labouring course, maternal or neonatal outcomes. The probability of vaginal delivery was independently related to the cervical length measured by transvaginal sonography 8 h after Prostin or Propess administration as well as neonatal birth weight. CONCLUSION: Both Prostin and Propess can be used as cervical ripening agents with similar efficacy and without significant morbidity. Propess administration was associated with higher vaginal delivery rate and less need to add oxytocin. Intrapartum measurement of cervical length is helpful in predicting successful vaginal delivery.


Assuntos
Dinoprostona , Ocitócicos , Recém-Nascido , Gravidez , Feminino , Humanos , Ocitocina , Estudos Prospectivos , Método Simples-Cego , Trabalho de Parto Induzido
2.
Int J Mol Sci ; 23(15)2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35955808

RESUMO

The Kaposi's sarcoma-associated herpesvirus (KSHV)-encoded ORF50 protein is a potent transcriptional activator essential for triggering KSHV lytic reactivation. Despite extensive studies, little is known about whether ORF50 possesses the ability to repress gene expression or has an antagonistic action to cellular transcription factors. Previously, we demonstrated that human oncoprotein MDM2 can promote the degradation of ORF50 protein. Herein, we show that abundant ORF50 expression in cells can conversely downregulate MDM2 expression via repressing both the upstream (P1) and internal (P2) promoters of the MDM2 gene. Deletion analysis of the MDM2 P1 promoter revealed that there were two ORF50-dependent negative response elements located from -102 to -63 and from -39 to +1, which contain Sp1-binding sites. For the MDM2 P2 promoter, the ORF50-dependent negative response element was identified in the region from -110 to -25, which is coincident with the location of two known p53-binding sites. Importantly, we further demonstrated that overexpression of Sp1 or p53 in cells indeed upregulated MDM2 expression; however, coexpression with ORF50 protein remarkably reduced the Sp1- or p53-mediated MDM2 upregulation. Collectively, our findings propose a reciprocal negative regulation between ORF50 and MDM2 and uncover that ORF50 decreases MDM2 expression through repressing Sp1- and p53-mediated transactivation.


Assuntos
Herpesvirus Humano 8 , Regulação Viral da Expressão Gênica , Herpesvirus Humano 8/genética , Humanos , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Elementos de Resposta , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/metabolismo , Fatores de Transcrição/metabolismo , Ativação Transcricional , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Virais
3.
J Virol ; 94(18)2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32641483

RESUMO

The Kaposi's sarcoma-associated herpesvirus (KSHV)-encoded open reading frame 50 (ORF50) protein is the key transactivator responsible for the latent-to-lytic switch. Here, we investigated the transcriptional activation of the ORF56 gene (encoding a primase protein) by ORF50 and successfully identified an ORF50-responsive element located in the promoter region between positions -97 and -44 (designated 56p-RE). This 56p-RE element contains a noncanonical RBP-Jκ-binding sequence and a nonconsensus Sp1/Sp3-binding sequence. Electrophoretic mobility shift assays revealed that RBP-Jκ, Sp3, and ORF50 could form stable complexes on the 56p-RE element. Importantly, transient-reporter analysis showed that Sp3, but not RBP-Jκ or Sp1, acts in synergy with ORF50 to activate the 56p-RE-containing reporter construct, and the synergy mainly depends on the Sp1/Sp3-binding region of the 56p-RE element. Sequence similarity searches revealed that the promoters for ORF21 (thymidine kinase), ORF60 (ribonucleotide reductase, small subunit), and cellular interleukin-10 (IL-10) contain a sequence motif similar to the Sp1/Sp3-binding region of the 56p-RE element, and we found that these promoters could also be synergistically activated by ORF50 and Sp3 via the conserved motifs. Noteworthily, the conversion of the Sp1/Sp3-binding sequence of the 56p-RE element into a consensus high-affinity Sp-binding sequence completely lost the synergistic response to ORF50 and Sp3. Moreover, transcriptional synergy could not be detected through other ORF50-responsive elements from the viral PAN, K12, ORF57, and K6 promoters. Collectively, the results of our study demonstrate that ORF50 and Sp3 can act in synergy on the transcription of specific gene promoters, and we find a novel conserved cis-acting motif in these promoters essential for transcriptional synergy.IMPORTANCE Despite the critical role of ORF50 in the KSHV latent-to-lytic switch, the molecular mechanism by which ORF50 activates its downstream target genes, especially those that encode the viral DNA replication enzymes, is not yet fully understood. Here, we find that ORF50 can cooperate with Sp3 to synergistically activate promoters of the viral ORF56 (primase), ORF21 (thymidine kinase), and ORF60 (ribonucleotide reductase) genes via similar Sp1/Sp3-binding motifs. Additionally, the same synergistic effect can be seen on the promoter of the cellular IL-10 gene. Overall, our data reveal an important role for Sp3 in ORF50-mediated transactivation, and we propose a new subclass of ORF50-responsive elements in viral and cellular promoters.


Assuntos
Herpesvirus Humano 8/genética , Proteínas Imediatamente Precoces/genética , Regiões Promotoras Genéticas , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp3/genética , Transativadores/genética , Transcrição Gênica , Animais , Sítios de Ligação , Linhagem Celular , Linhagem Celular Tumoral , Células Clonais , Fibroblastos/virologia , Regulação da Expressão Gênica , Células HEK293 , Herpesvirus Humano 8/metabolismo , Interações Hospedeiro-Patógeno/genética , Humanos , Proteínas Imediatamente Precoces/metabolismo , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/genética , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/metabolismo , Interleucina-10/genética , Interleucina-10/metabolismo , Linfócitos/virologia , Camundongos , Ligação Proteica , Elementos de Resposta , Transdução de Sinais , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição Sp3/metabolismo , Transativadores/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo , Proteínas Virais Reguladoras e Acessórias/genética , Proteínas Virais Reguladoras e Acessórias/metabolismo
4.
Infection ; 49(1): 135-144, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33389697

RESUMO

STUDY OBJECTIVE: Necrotizing fasciitis (NF) is an uncommon life-threatening necrotizing skin and soft tissue infection. Bullae are special skin manifestations of NF. This study was conducted to analyze the differences between different types of bullae of limbs with NF for providing the information to emergency treatment. METHODS: From April 2015 to August 2018, patients were initially enrolled based on surgical confirmation of limbs with NF. According to the presence of different bullae types, patients were divided into no bullae group (Group N), serous-filled bullae group (Group S), and hemorrhagic bullae group (Group H). Data such as demographics, clinical outcomes, microbiological results, presenting symptoms/signs, and laboratory findings were compared among these groups. RESULTS: In total, 187 patients were collected, with 111 (59.4%) patients in Group N, 35 (18.7%) in Group S, and 41 (21.9%) in Group H. Group H had the highest incidence of amputation, required intensive care unit care, and most patients infected with Vibrio species. In Group N, more patients were infected with Staphylococcus spp. than Group H. In Group S, more patients were infected with ß-hemolytic Streptococcus than Group H. Patients with bacteremia, shock, skin necrosis, anemia, and longer prothrombin time constituted higher proportions in Group H and S than in Group N. CONCLUSIONS: In southern Taiwan, patients with NF accompanied by hemorrhagic bullae appear to have more bacteremia, Vibrio infection, septic shock, and risk for amputation. If the physicians at the emergency department can detect for the early signs of NF as soon as possible, and more patient's life and limbs may be saved.


Assuntos
Vesícula , Fasciite Necrosante , Idoso , Idoso de 80 Anos ou mais , Amputação Cirúrgica/estatística & dados numéricos , Bacteriemia/epidemiologia , Vesícula/complicações , Vesícula/epidemiologia , Vesícula/terapia , Fasciite Necrosante/complicações , Fasciite Necrosante/epidemiologia , Fasciite Necrosante/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Choque Séptico/epidemiologia , Infecções dos Tecidos Moles/complicações , Infecções dos Tecidos Moles/epidemiologia , Infecções dos Tecidos Moles/terapia , Taiwan
5.
Int J Mol Sci ; 22(8)2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33919712

RESUMO

The unfolded protein response (UPR) is an intracellular signaling pathway essential for alleviating the endoplasmic reticulum (ER) stress. To support the productive infection, many viruses are known to use different strategies to manipulate the UPR signaling network. However, it remains largely unclear whether the UPR signaling pathways are modulated in the lytic cycle of Epstein-Barr virus (EBV), a widely distributed human pathogen. Herein, we show that the expression of GRP78, a central UPR regulator, is up-regulated during the EBV lytic cycle. Our data further revealed that knockdown of GRP78 in EBV-infected cell lines did not substantially affect lytic gene expression; however, GRP78 knockdown in these cells markedly reduced the production of virus particles. Importantly, we identified that the early lytic protein BMLF1 is the key regulator critically contributing to the activation of the grp78 gene promoter. Mechanistically, we found that BMLF1 can trigger the proteolytic cleavage and activation of the UPR senor ATF6, which then transcriptionally activates the grp78 promoter through the ER stress response elements. Our findings therefore provide evidence for the connection between the EBV lytic cycle and the UPR, and implicate that the BMLF1-mediated ATF6 activation may play critical roles in EBV lytic replication.


Assuntos
Fator 6 Ativador da Transcrição/metabolismo , Proteínas de Choque Térmico/genética , Fosfoproteínas/metabolismo , Transativadores/metabolismo , Regulação para Cima , Sequência de Bases , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , DNA Viral/biossíntese , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Endorribonucleases/metabolismo , Regulação Viral da Expressão Gênica , Células HEK293 , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/fisiologia , Humanos , Modelos Biológicos , Regiões Promotoras Genéticas , Proteínas Serina-Treonina Quinases/metabolismo , Transporte Proteico , Transdução de Sinais , Ativação Transcricional/genética , Resposta a Proteínas não Dobradas , Regulação para Cima/genética , eIF-2 Quinase/metabolismo
6.
BMC Infect Dis ; 20(1): 60, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959118

RESUMO

BACKGROUND: Necrotizing fasciitis (NF) is a rare and life-threatening necrotizing skin and soft-tissue infection. Infectious pathogens of NF must be detected early and treated rapidly to prevent loss of limb or a fatal outcome. This study aimed to detect more reliable predictors between gram-negative and gram-positive monomicrobial NF of limbs. METHODS: A total of 100 patients with limb monomicrobial NF were diagnosed prospectively from April 2015 to July 2018. These monomicrobial NF pathogens can be divided into gram-negative and gram-positive groups according to the result of Gram staining and final bacterial reports. Data such as demographics, seawater or seafood contact history, infectious location, comorbidities, presenting signs and symptoms, and laboratory findings were recorded and compared. RESULTS: A total of 55 patients were infected with gram-negative organisms and 45 patients with gram-positive organisms. Among the 55 cases of monomicrobial gram-negative NF, 48 (87.3%) were caused mainly by Vibrio spp. (38, 69.1%) and Aeromonas spp. (10, 18.2%). A higher incidence of chronic kidney disease, cerebrovascular accident, tachypnea, and septic shock; a higher rate of band forms of leukocytes of more than 3%, serum lactate of more than 20 mg/dL, and C-reactive protein level of less than 150 mg/dL; prolonged prothrombin time; and a lower fibrinogen level were observed in patients with gram-negative infection. In a multivariate analysis, a higher incidence of seawater or seafood contact history (odds ratio [OR]: 66.301; 95% confidence interval [CI]: 7.467-588.702), a higher rate of hyperlactatemia (OR: 7.904; 95% CI: 1.231-50.744), and a low fibrinogen level (OR: 1.013; 95% CI: 1.004-1.023) indicated gram-negative infection. CONCLUSIONS: In southern Taiwan, NF of limbs mainly affected the lower limbs, exhibited monomicrobial infection, and was predominated by gram-negative bacteria. Gram-negative monomicrobial NF of limbs often occurred in individuals with the more seawater or seafood contact history, hyperlactatemia, and low fibrinogen levels.


Assuntos
Aeromonas/isolamento & purificação , Fasciite Necrosante/epidemiologia , Fasciite Necrosante/microbiologia , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções dos Tecidos Moles/epidemiologia , Infecções dos Tecidos Moles/microbiologia , Vibrio/isolamento & purificação , Idoso , Idoso de 80 Anos ou mais , Fasciite Necrosante/diagnóstico , Feminino , Infecções por Bactérias Gram-Negativas/diagnóstico , Humanos , Incidência , Extremidade Inferior/microbiologia , Extremidade Inferior/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Infecções dos Tecidos Moles/diagnóstico , Taiwan/epidemiologia
7.
Molecules ; 25(22)2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33202823

RESUMO

Genetic mutations accumulated overtime could generate many growth and survival advantages for cancer cells, but these mutations also mark cancer cells as targets to be eliminated by the immune system. To evade immune surveillance, cancer cells adopted different intrinsic molecules to suppress immune response. PD-L1 is frequently overexpressed in many cancer cells, and its engagement with PD-1 on T cells diminishes the extent of cytotoxicity from the immune system. To resume immunity for fighting cancer, several therapeutic antibodies disrupting the PD-1/PD-L1 interaction have been introduced in clinical practice. However, their immunogenicity, low tissue penetrance, and high production costs rendered these antibodies beneficial to only a limited number of patients. PD-L1 dimer formation shields the interaction interface for PD-1 binding; hence, screening for small molecule compounds stabilizing the PD-L1 dimer may make immune therapy more effective and widely affordable. In the current study, 111 candidates were selected from over 180,000 natural compound structures through virtual screening, contact fingerprint analysis, and pharmacological property prediction. Twenty-two representative candidates were further evaluated in vitro. Two compounds were found capable of inhibiting the PD-1/PD-L1 interaction and promoting PD-L1 dimer formation. Further structure optimization and clinical development of these lead inhibitors will eventually lead to more effective and affordable immunotherapeutic drugs for cancer patients.


Assuntos
Produtos Biológicos/farmacologia , Neoplasias/tratamento farmacológico , Receptor de Morte Celular Programada 1/química , Anticorpos/uso terapêutico , Antineoplásicos Imunológicos/química , Antígeno B7-H1/química , Análise por Conglomerados , Reagentes de Ligações Cruzadas/química , Bases de Dados Factuais , Avaliação Pré-Clínica de Medicamentos , Humanos , Ligação de Hidrogênio , Imunoterapia , Simulação de Acoplamento Molecular , Mutação , Polímeros/uso terapêutico , Ligação Proteica , Multimerização Proteica , Bibliotecas de Moléculas Pequenas/química
8.
J Virol ; 92(5)2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29212938

RESUMO

The genotype II.4 (GII.4) variants of human noroviruses (HuNVs) are recognized as the major agent of global gastroenteritis outbreaks. Due to the lack of an efficient cell culture system for HuNV propagation, the exact roles of HuNV-encoded nonstructural proteins (including Nterm, NTPase, P22, VPg, Pro, and RdRp) in viral replication or pathogenesis have not yet been fully understood. Here, we report the molecular characterization of the GII.4 HuNV-encoded NTPase (designated GII-NTPase). Results from our studies showed that GII-NTPase forms vesicular or nonvesicular textures in the cell cytoplasm, and the nonvesicular fraction of GII-NTPase significantly localizes to the endoplasmic reticulum (ER) or mitochondria. Deletion analysis revealed that the N-terminal 179-amino-acid (aa) region of GII-NTPase is required for vesicle formation and for ER colocalization, whereas the C-terminal region is involved in mitochondrial colocalization. In particular, two mitochondrion-targeting domains were identified in the C-terminal region of GII-NTPase which perfectly colocalized with mitochondria when the N-terminal region of GII-NTPase was deleted. However, the corresponding C-terminal portions of NTPase derived from the GI HuNV did not show mitochondrial colocalization. We also found that GII-NTPase physically interacts with itself as well as with Nterm and P22, but not VPg, Pro, and RdRp, in cells. The Nterm- and P22-interacting region was mapped to the N-terminal 179-aa region of GII-NTPase, whereas the self-assembly of GII-NTPase could be achieved via a head-to-head, tail-to-tail, or head-to-tail configuration. More importantly, we demonstrate that GII-NTPase possesses a proapoptotic activity, which can be further enhanced by coexpression with Nterm or P22.IMPORTANCE Despite the importance of human norovirus GII.4 variants in global gastroenteritis outbreaks, the basic biological functions of the viral nonstructural proteins in cells remain rarely investigated. In this report, we focus our studies on characteristics of the GII.4 norovirus-encoded NTPase (GII-NTPase). We unexpectedly find that GII-NTPase can perfectly colocalize with mitochondria after its N-terminal region is deleted. However, such a phenomenon is not observed for NTPase encoded by a GI strain. We further reveal that the N-terminal 179-aa region of GII-NTPase is sufficient to mediate (i) vesicle formation, (ii) ER colocalization, (iii) the interaction with two other nonstructural proteins, including Nterm and P22, (iv) the formation of homodimers or homo-oligomers, and (v) the induction of cell apoptosis. Taken together, our findings emphasize that the virus-encoded NTPase must have multiple activities during viral replication or pathogenesis; however, these activities may vary somewhat among different genogroups.


Assuntos
Norovirus/enzimologia , Norovirus/genética , Nucleosídeo-Trifosfatase/genética , Nucleosídeo-Trifosfatase/metabolismo , Sequência de Aminoácidos , Apoptose , Infecções por Caliciviridae/virologia , Mapeamento Cromossômico , Citoplasma/metabolismo , Surtos de Doenças , Retículo Endoplasmático/metabolismo , Gastroenterite/virologia , Genótipo , Células HEK293 , Humanos , Mitocôndrias/metabolismo , Norovirus/classificação , Norovirus/patogenicidade , Nucleosídeo-Trifosfatase/química , Nucleosídeo-Trifosfatase/imunologia , Domínios e Motivos de Interação entre Proteínas , Alinhamento de Sequência , Deleção de Sequência , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Replicação Viral
9.
Int J Mol Sci ; 20(20)2019 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-31614930

RESUMO

The tumor microenvironment, which consists of fibroblasts, smooth muscle cells, endothelial cells, immune cells, epithelial cells, and extracellular matrices, plays a crucial role in tumor progression. Hepatic stellate cells (HSCs), a class of unique liver stromal cells, participate in immunomodulatory activities by inducing the apoptosis of effector T-cells, generation of regulatory T-cells, and development of myeloid-derived suppressor cells (MDSCs) to achieve long-term survival of islet allografts. This study provides in vitro and in vivo evidences that HSCs induce the generation of MDSCs to promote hepatocellular carcinoma (HCC) progression through interleukin (IL)-6 secretion. HSC-induced MDSCs highly expressed inducible nitric oxide synthase (iNOS) and arginase 1 mRNA and presented potent inhibitory T-cell immune responses in the tumor environment. Wild-type HSC-induced MDSCs expressed lower levels of CD40, CD86, and MHC II, and a higher level of B7-H1 surface molecules, as well as increased the production of iNOS and arginase I compared with MDSCs induced by IL-6-deficient HSCs in vitro. A murine-transplanted model of the liver tumor showed that HCCs cotransplanted with HSCs could significantly enhance the tumor area and detect more MDSCs compared with HCCs alone or HCCs cotransplanted with HSCs lacking IL-6. In conclusion, the results indicated that MDSCs are induced mainly by HSCs through IL-6 signaling and produce inhibitory enzymes to reduce T-cell immunity and then promote HCC progression within the tumor microenvironment. Therapies targeting the pathway involved in MDSC production or its immune-modulating pathways can serve as an alternative immunotherapy for HCC.


Assuntos
Células Estreladas do Fígado/metabolismo , Interleucina-6/metabolismo , Neoplasias Hepáticas Experimentais/imunologia , Células Supressoras Mieloides/imunologia , Animais , Arginase/metabolismo , Linhagem Celular , Progressão da Doença , Humanos , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/citologia , Monócitos/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Transdução de Sinais , Linfócitos T/metabolismo , Microambiente Tumoral/imunologia
10.
J Virol ; 91(19)2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28701396

RESUMO

The switch of Kaposi's sarcoma-associated herpesvirus (KSHV) from latency to lytic replication is a key event for viral dissemination and pathogenesis. MLN4924, a novel neddylation inhibitor, reportedly causes the onset of KSHV reactivation but impairs later phases of the viral lytic program in infected cells. Thus far, the molecular mechanism involved in the modulation of the KSHV lytic cycle by MLN4924 is not yet fully understood. Here, we confirmed that treatment of different KSHV-infected primary effusion lymphoma (PEL) cell lines with MLN4924 substantially induces viral lytic protein expression. Due to the key role of the virally encoded ORF50 protein in the latent-to-lytic switch, we investigated its transcriptional regulation by MLN4924. We found that MLN4924 activates the ORF50 promoter (ORF50p) in KSHV-positive cells (but not in KSHV-negative cells), and the RBP-Jκ-binding elements within the promoter are critically required for MLN4924 responsiveness. In KSHV-negative cells, reactivation of the ORF50 promoter by MLN4924 requires the presence of the latency-associated nuclear antigen (LANA). Under such a condition, LANA acts as a repressor to block the ORF50p activity, whereas MLN4924 treatment relieves LANA-mediated repression. Importantly, we showed that LANA is a neddylated protein and can be deneddylated by MLN4924. On the other hand, we revealed that MLN4924 exhibits concentration-dependent biphasic effects on 12-O-tetradecanoylphorbol-13-acetate (TPA)- or sodium butyrate (SB)-induced viral reactivation in PEL cell lines. In other words, low concentrations of MLN4924 promote activation of TPA- or SB-mediated viral reactivation, whereas high concentrations of MLN4924, conversely, inhibit the progression of TPA- or SB-mediated viral lytic program.IMPORTANCE MLN4924 is a neddylation (NEDD8 modification) inhibitor, which currently acts as an anti-cancer drug in clinical trials. Although MLN4924 has been reported to trigger KSHV reactivation, many aspects regarding the action of MLN4924 in regulating the KSHV lytic cycle are not fully understood. Since the KSHV ORF50 protein is the key regulator of viral lytic reactivation, we focus on its transcriptional regulation by MLN4924. We here show that activation of the ORF50 gene by MLN4924 involves the relief of LANA-mediated transcriptional repression. Importantly, we find that LANA is a neddylated protein. To our knowledge, this is the first report showing that neddylation occurs in viral proteins. Additionally, we provide evidence that different concentrations of MLN4924 have opposite effects on TPA-mediated or SB-mediated KSHV lytic cycle activation. Therefore, in clinical application, we propose that MLN4924 needs to be used with caution in combination therapy to treat KSHV-positive subjects.


Assuntos
Ciclopentanos/farmacologia , Herpesvirus Humano 8/patogenicidade , Proteínas Imediatamente Precoces/genética , Pirimidinas/farmacologia , Sarcoma de Kaposi/patologia , Transativadores/genética , Enzimas Ativadoras de Ubiquitina/antagonistas & inibidores , Ativação Viral/efeitos dos fármacos , Antígenos Virais/metabolismo , Ácido Butírico/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Células HEK293 , Humanos , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/genética , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/metabolismo , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas/efeitos dos fármacos , Sarcoma de Kaposi/virologia , Acetato de Tetradecanoilforbol/farmacologia
11.
Planta Med ; 84(15): 1110-1117, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29763944

RESUMO

Baicalin is the main flavonoid from the roots of an important medicinal plant, Scutellaria baicalensis, which shows a variety biological activities. Psoriasis is a chronic immune-mediated inflammatory disease that affects the skin. The unmet need of psoriasis is that many patients do not respond adequately to available clinical treatment. In this study, we found that baicalin showed inhibited dermal inflammation in a murine model of psoriasis via topical application of imiquimod. After a 5-day topical imiquimod application, baicalin or the control vehicle cream was to applied to the lesions of BALB/c mice for a further 4 days. The erythema, scaling, and thickness of the epidermal layer significantly improved in the baicalin-treated mice. The levels of interleukin-17A, interleukin-22, interleukin-23, and tumor necrosis factor in the skin significantly decreased after baicalin treatment. Baicalin also inhibited imiquimod-induced interleukin-17A production in skin draining lymph node cells. The infiltration of γδ T cells into the skin lesions induced by imiquimod was also suppressed after baicalin treatment. These results suggest that baicalin inhibited skin inflammation through the inhibition of the interleukin-17/interleukin-23 axis in a murine model of psoriasis.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Citocinas/metabolismo , Toxidermias/tratamento farmacológico , Flavonoides/farmacologia , Psoríase/tratamento farmacológico , Aminoquinolinas/efeitos adversos , Animais , Anti-Inflamatórios não Esteroides/química , Modelos Animais de Doenças , Toxidermias/patologia , Feminino , Flavonoides/química , Humanos , Imiquimode , Interleucina-17/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Psoríase/patologia , Receptores de Interleucina/metabolismo , Pele/patologia
12.
J Cell Physiol ; 232(12): 3309-3316, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28059450

RESUMO

KCNQ1 encodes a potassium voltage-gated channel and represents a susceptibility locus for type 2 diabetes mellitus (T2DM). Here, we explored the association between KCNQ1 polymorphisms and hypertension risk in individuals with T2DM, as well as the role of KCNQ1 in vascular smooth muscle cell contraction in vitro. To investigate the relationship between KCNQ1 and the risk of developing hypertension in patients with T2DM, we divided the T2DM cohort into hypertension (n = 452) and non-hypertension (n = 541) groups. The Mann-Whitney U test, chi-square test, and multivariate regression analyses were used to assess the clinical characteristics and genotypic frequencies. In vitro studies utilized the rat aortic smooth muscle A10 cell line. Patients in the hypertension group were significantly older at the time of enrollment and had higher levels of body mass index, waist-to-hip ratio, and triglyceride than those in the non-hypertension group. The KCNQ1 rs3864884 and rs12576239 genetic variants were associated with hypertension in T2DM. KCNQ1 expression was lower in the individuals with the CC versus the CT and TT genotypes. Smooth muscle cell contractility was inhibited by treatment with a KCNQ1 inhibitor. These results suggest that KCNQ1 might be associated with hypertension in individuals with T2DM.


Assuntos
Diabetes Mellitus Tipo 2/genética , Variação Genética , Hipertensão/genética , Canal de Potássio KCNQ1/genética , Músculo Liso/fisiologia , Idoso , Animais , Linhagem Celular , Diabetes Mellitus Tipo 2/complicações , Feminino , Genótipo , Humanos , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Contração Muscular , Ratos
13.
J Virol ; 88(20): 12133-45, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25122800

RESUMO

Autophagy is an intracellular degradation pathway that provides a host defense mechanism against intracellular pathogens. However, many viruses exploit this mechanism to promote their replication. This study shows that lytic induction of Epstein-Barr virus (EBV) increases the membrane-bound form of LC3 (LC3-II) and LC3-containing punctate structures in EBV-positive cells. Transfecting 293T cells with a plasmid that expresses Rta also induces autophagy, revealing that Rta is responsible for autophagic activation. The activation involves Atg5, a key component of autophagy, but not the mTOR pathway. The expression of Rta also activates the transcription of the genes that participate in the formation of autophagosomes, including LC3A, LC3B, and ATG9B genes, as well as those that are involved in the regulation of autophagy, including the genes TNF, IRGM, and TRAIL. Additionally, treatment with U0126 inhibits the Rta-induced autophagy and the expression of autophagy genes, indicating that the autophagic activation is caused by the activation of extracellular signal-regulated kinase (ERK) signaling by Rta. Finally, the inhibition of autophagic activity by an autophagy inhibitor, 3-methyladenine, or Atg5 small interfering RNA, reduces the expression of EBV lytic proteins and the production of viral particles, revealing that autophagy is critical to EBV lytic progression. This investigation reveals how an EBV-encoded transcription factor promotes autophagy to affect viral lytic development.


Assuntos
Autofagia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Herpesvirus Humano 4/imunologia , Proteínas Imediatamente Precoces/fisiologia , Transativadores/fisiologia , Sequência de Bases , Primers do DNA , Células HEK293 , Humanos , Microscopia Eletrônica de Transmissão , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais
14.
J Virol ; 88(17): 10092-109, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-24965448

RESUMO

UNLABELLED: The orf47-orf46-orf45 gene cluster of Kaposi's sarcoma-associated herpesvirus (KSHV) is known to serially encode glycoprotein L (gL), uracil DNA glycosylase, and a viral tegument protein. Here, we identify two novel mRNA variants, orf47/45-A and orf47/45-B, alternatively spliced from a tricistronic orf47-orf46-orf45 mRNA that is expressed in the orf47-orf46-orf45 gene locus during the early stages of viral reactivation. The spliced gene products, ORF47/45-A and ORF47/45-B, consist of only a partial region of gL (ORF47), a unique 7-amino-acid motif, and the complete tegument protein ORF45. Like the ORF45 protein, ORF47/45-A and ORF47/45-B expressed in cells sufficiently activate the phosphorylation of p90 ribosomal S6 kinase (RSK) and extracellular signal-regulated protein kinase (ERK). However, unlike ORF45, both ORF47/45-A and ORF47/45-B contain a signal peptide sequence and are localized at the endoplasmic reticulum (ER). Additionally, we found that ORF47/45-A and ORF47/45-B have an extra function that mediates the upregulation of GRP78, a master regulator of ER homeostasis. The important event regarding GRP78 upregulation can be observed in all tested KSHV-positive cell lines after viral reactivation, and knockdown of GRP78 in cells significantly impairs viral lytic cycle progression, especially at late lytic stages. Compared with some other viral glycoproteins synthesized through the ER, our results strongly implicate that the ORF47/45 proteins may serve as key effectors for controlling GRP78 expression and ER homeostasis in cells. Taken together, our findings provide evidence showing the reciprocal association between the modulation of ER homeostasis and the progression of the KSHV lytic cycle. IMPORTANCE: Emerging evidence has shown that several viruses appear to use different strategies to control ER homeostasis for supporting their productive infections. The two parts of this study identify two aspects of the association between the regulation of ER homeostasis and the progression of the KSHV lytic cycle. The first part characterizes the function of two early lytic cycle proteins, ORF47/45-A and ORF47/45-B, on the activation of a major ER chaperone protein, GRP78. In addition to the ability to promote GRP78 upregulation, the ORF47/45 proteins also activate the phosphorylation of RSK and ERK. The second part reveals that upregulation of GRP78 is essential for the progression of the KSHV lytic cycle, especially at late stages. We therefore propose that activation of GRP78 expression by viral proteins at the early lytic stage may aid with the protection of host cells from severe ER stress and may directly involve the assembly or release of virions.


Assuntos
DNA Recombinante , Genes Virais , Herpesvirus Humano 8/genética , Proteínas Imediatamente Precoces/genética , Família Multigênica , DNA Viral/química , DNA Viral/genética , Chaperona BiP do Retículo Endoplasmático , Regulação Viral da Expressão Gênica , Herpesvirus Humano 8/fisiologia , Humanos , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Viral/genética , Análise de Sequência de DNA , Replicação Viral
15.
J Clin Lab Anal ; 28(6): 461-4, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24659220

RESUMO

BACKGROUND: Kawasaki disease (KD) is an acute, self-limited vasculitis in infants and young children. Interleukin-10 (IL-10) is a potent cytokine that exerts pleiotropic effects on immunoregulation and inflammation. Elevated IL-10 serum levels have been reported in the KD patients. METHODS: In this study, we investigated whether IL-10 genetic polymorphisms contribute to coronary artery aneurysm (CAA) development among KD patients in Taiwan. A total of 58 KD patients with CAA and 277 unrelated healthy children matched for sex and age were enrolled for this study. RESULTS: Higher G allele frequencies of IL-10 at -1082 position were observed in KD patients with CAA compared to the controls (P = 0.016, OR: 2.86, 95% CI, 1.17-6.98). In addition, higher IL-10 GCC haplotype frequencies were also observed in KD patients with CAA (P = 0.016, OR: 2.85, 95% CI, 1.17-6.98). CONCLUSION: Our data support the possibility that IL-10 gene polymorphisms may be related with CAA development of KD in Taiwanese population.


Assuntos
Aneurisma Coronário/genética , Interleucina-10/genética , Síndrome de Linfonodos Mucocutâneos/complicações , Regiões Promotoras Genéticas/genética , Estudos de Casos e Controles , Criança , Pré-Escolar , Aneurisma Coronário/complicações , Feminino , Frequência do Gene , Haplótipos , Humanos , Lactente , Masculino , Síndrome de Linfonodos Mucocutâneos/genética , Polimorfismo Genético , Taiwan
16.
Virus Res ; 345: 199379, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38643859

RESUMO

Although all herpesviruses utilize a highly conserved replication machinery to amplify their viral genomes, different members may have unique strategies to modulate the assembly of their replication components. Herein, we characterize the subcellular localization of seven essential replication proteins of varicella-zoster virus (VZV) and show that several viral replication enzymes such as the DNA polymerase subunit ORF28, when expressed alone, are localized in the cytoplasm. The nuclear import of ORF28 can be mediated by the viral DNA polymerase processivity factor ORF16. Besides, ORF16 could markedly enhance the protein abundance of ORF28. Noteworthily, an ORF16 mutant that is defective in nuclear transport still retained the ability to enhance ORF28 abundance. The low abundance of ORF28 in transfected cells was due to its rapid degradation mediated by the ubiquitin-proteasome system. We additionally reveal that radicicol, an inhibitor of the chaperone Hsp90, could disrupt the interaction between ORF16 and ORF28, thereby affecting the nuclear entry and protein abundance of ORF28. Collectively, our findings imply that the cytoplasmic retention and rapid degradation of ORF28 may be a key regulatory mechanism for VZV to prevent untimely viral DNA replication, and suggest that Hsp90 is required for the interaction between ORF16 and ORF28.


Assuntos
Transporte Ativo do Núcleo Celular , DNA Polimerase Dirigida por DNA , Herpesvirus Humano 3 , Proteínas Virais , Replicação Viral , Herpesvirus Humano 3/genética , Herpesvirus Humano 3/metabolismo , Humanos , Proteínas Virais/metabolismo , Proteínas Virais/genética , DNA Polimerase Dirigida por DNA/metabolismo , DNA Polimerase Dirigida por DNA/genética , Núcleo Celular/metabolismo , Núcleo Celular/virologia , Citoplasma/metabolismo , Citoplasma/virologia , Linhagem Celular , Replicação do DNA
17.
J Virol ; 86(18): 9647-55, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22740416

RESUMO

Epstein-Barr virus (EBV) BBLF1 shares 13 to 15% amino acid sequence identities with the herpes simplex virus 1 UL11 and cytomegalovirus UL99 tegument proteins, which are involved in the final envelopment during viral maturation. This study demonstrates that BBLF1 is a myristoylated and palmitoylated protein, as are UL11 and UL99. Myristoylation of BBLF1 both facilitates its membrane anchoring and stabilizes it. BBLF1 is shown to localize to the trans-Golgi network (TGN) along with gp350/220, a site where final envelopment of EBV particles takes place. The localization of BBLF1 at the TGN requires myristoylation and two acidic clusters, which interact with PACS-1, a cytosolic protein, to mediate retrograde transport from the endosomes to the TGN. Knockdown of the expression of BBLF1 during EBV lytic replication reduces the production of virus particles, demonstrating the requirement of BBLF1 to achieve optimal production of virus particles. BBLF1 is hypothesized to facilitate the budding of tegumented capsid into glycoprotein-embedded membrane during viral maturation.


Assuntos
Herpesvirus Humano 4/fisiologia , Proteínas Virais/fisiologia , Sequência de Aminoácidos , Sequência de Bases , Transporte Biológico Ativo , DNA Viral/genética , Técnicas de Silenciamento de Genes , Células HEK293 , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/patogenicidade , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Lipoilação , Dados de Sequência Molecular , Ácido Mirístico/química , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteínas Virais/química , Proteínas Virais/genética , Replicação Viral , Rede trans-Golgi/virologia
18.
J Pediatr Gastroenterol Nutr ; 57(2): 225-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23880628

RESUMO

OBJECTIVE: Gastrointestinal (GI) involvement in childhood Behçet disease (BD) is not well understood. We aimed to clarify the intestinal presentation in children with BD. METHODS: Medical records of 85 children with recurrent oral ulcers between 1990 and 2010 at the National Taiwan University Hospital were reviewed retrospectively. Twenty of them who fulfilled the Mason and Barnes criteria for the diagnosis of childhood BD were enrolled. The clinical and laboratory characteristics were analyzed. RESULTS: Among 20 patients, the median age at diagnosis was 13.2 years. The common presentations included oral ulcers (100%), genital ulcers (70%), skin lesions (65%), and GI symptoms (50%). Five of 10 patients with GI symptoms received endoscopic examinations and all had ulcers. Divided by the age of 10, patients younger than 10 years tended to have higher rates of GI symptoms initially and intestinal ulcers (P = 0.002 and 0.015, respectively). Platelet count was significantly lower in young patients (P = 0.0151). Patients without GI symptoms had higher rates of skin involvement than patients with GI symptoms (P = 0.019). CONCLUSIONS: Young children with BD tended to have more GI presentations. For children with BD younger than 10 years having GI symptoms, endoscopic examinations may be considered.


Assuntos
Síndrome de Behçet/patologia , Gastroenteropatias/etiologia , Boca/patologia , Úlceras Orais/etiologia , Dermatopatias/etiologia , Pele/patologia , Úlcera/etiologia , Adolescente , Fatores Etários , Criança , Pré-Escolar , Endoscopia , Feminino , Gastroenteropatias/epidemiologia , Genitália/patologia , Humanos , Lactente , Masculino , Úlceras Orais/epidemiologia , Contagem de Plaquetas , Dermatopatias/epidemiologia , Taiwan/epidemiologia , Úlcera/epidemiologia
19.
Cells ; 12(11)2023 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-37296628

RESUMO

Type 1 diabetes is an inflammatory state. Myeloid-derived suppressive cells (MDSCs) originate from immature myeloid cells and quickly expand to control host immunity during infection, inflammation, trauma, and cancer. This study presents an ex vivo procedure to develop MDSCs from bone marrow cells propagated from granulocyte-macrophage-colony-stimulating factor (GM-CSF), interleukin (IL)-6, and IL-1ß cytokines expressing immature morphology and high immunosuppression of T-cell proliferation. The adoptive transfer of cytokine-induced MDSCs (cMDSCs) improved the hyperglycemic state and prolonged the diabetes-free survival of nonobese diabetic (NOD) mice with severe combined immune deficiency (SCID) induced by reactive splenic T cells harvested from NOD mice. In addition, the application of cMDSCs reduced fibronectin production in the renal glomeruli and improved renal function and proteinuria in diabetic mice. Moreover, cMDSCs use mitigated pancreatic insulitis to restore insulin production and reduce the levels of HbA1c. In conclusion, administering cMDSCs propagated from GM-CSF, IL-6, and IL-1ß cytokines provides an alternative immunotherapy protocol for treating diabetic pancreatic insulitis and renal nephropathy.


Assuntos
Diabetes Mellitus Experimental , Células Supressoras Mieloides , Camundongos , Animais , Citocinas/farmacologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Diabetes Mellitus Experimental/terapia , Camundongos Endogâmicos NOD
20.
Microbiol Spectr ; 11(6): e0225423, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37874136

RESUMO

IMPORTANCE: Eukaryotic DNA replication is a highly regulated process that requires multiple replication enzymes assembled onto DNA replication origins. Due to the complexity of the cell's DNA replication machinery, most of what we know about cellular DNA replication has come from the study of viral systems. Herein, we focus our study on the assembly of the Kaposi's sarcoma-associated herpesvirus core replication complex and propose a pairwise protein-protein interaction network of six highly conserved viral core replication proteins. A detailed understanding of the interaction and assembly of the viral core replication proteins may provide opportunities to develop new strategies against viral propagation.


Assuntos
Herpesvirus Humano 8 , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/metabolismo , Proteínas Virais/genética , Replicação do DNA
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